Unfortunately we can’t reproduce this problem. It’s working fine on multiple devices and different screens.
You may check top margin that is added to banner on the home page (margin is added to push banner below static menu) and check the values, maybe margin isn’t calculated right if for some reason height of header changes after margin of banner is already calculated.
In screenshot you send us I see that you didn’t close Envato’s top bar, you need to close it and check again because Demo is opened in iframe and responsive and some other stuff won’t work right.
Vladimir
